Using a PC power supply as a standalone?

Discussion in 'Tech Talk' started by fireguy129, Feb 27, 2010.

  1. fireguy129

    fireguy129

    Messages:
    1,893
    Likes Received:
    302
    Joined:
    May 31, 2001
    Location:
    Northeast Pa, usa
    My old desktop recently gave up the ghost, so in the process of pulling components I started wondering: Is it possible to use the power supply to power small 12vdc items off house current? It looks like the output will work with what I want, but in my haste I didn't pay attention to the wiring. I can identify the outputs, but I lost the switch leads to turn it on. Any ideas on how to identify them? I searched for a wiring diagram without any luck.
     
  2. HKUSP45Css

    HKUSP45Css

    Messages:
    3,969
    Likes Received:
    8
    Joined:
    Apr 4, 2007
    Location:
    Houston, by God, Texas
    The problem with ATX power supplys is, they're either always on or alwats off if they aren't plugged into a mobo. You can bend a paper clip to complete the green/black circuit and get power to it when you plug it in.

    If your ATX PS has a power switch on the back you could use that as the actuator.

    Find the green wire. If the wires aren't colored, look for the "PS-ON" socket, socket 14 on a 20-pin connector and socket 16 on a 24-pin connector. Now find the black or "ground" wire (located next to the green wire on either side), and get ready to bridge the connection.

    once bridged it will turn on when apply power.
     

  3. fireguy129

    fireguy129

    Messages:
    1,893
    Likes Received:
    302
    Joined:
    May 31, 2001
    Location:
    Northeast Pa, usa
    Fantastic, thank you!!
     
  4. JimmyN

    JimmyN

    Messages:
    1,266
    Likes Received:
    7
    Joined:
    Sep 29, 2006
    Location:
    Virginia
    I've converted several PC power supplies to power 12V battery chargers for RC use.

    Some will require a load on the 5V rail or they won't switch on. If you ground the green "power on" lead and you don't have any 12V output try putting a load on the 5V. I used a 6V lantern bulb across the 5V, which also gave me a "power on" light for the supply.
     
  5. HKUSP45Css

    HKUSP45Css

    Messages:
    3,969
    Likes Received:
    8
    Joined:
    Apr 4, 2007
    Location:
    Houston, by God, Texas